Method and means for purging thermostats



May 30, 1939. L, M. PERsoNS METHOD AND MEANS FOR PURGING THERMOSTATS Filed De. 19, 1936 2 Sheets-Sheet l May 30, 1939. l.. M. PERSONS 2,150,280

METHOD AND MEANS FOR PURGING THERMOSTATS Filed Dec. 19, 1936 2 Sheets-Sheet 2 Patented May-30, 1939 UNITED ASTATES PATENT OFFICE METHOD AND lWEANS FOR PURGING THERMOSTATS Delaware Application December 19, 1936, Serial No. 116,700

14 Claims.

The present invention relates to a novel method of making thermostatic elements or assemblies, and to a means for carrying out the method. More specifically, the present invention comprehends a novel way of removing air from liquid or fluid-filled thermostatic elements and byA centrifuge means.

Thermostatic elements heretofore have ordinarily comprised tubes at the end of which was attached some power means in the form of a bellows, diaphragm,v or the like, these power means extending laterally from one end of the tubes and in most instances involving pockets wherein air, or whatever fluid sought to be purged from the device could become entrapped. These pockets were so located that the ordinary centrifuge, providing'rotation about a single axis, was ineffective to eliminate all of the undesired air. Mechanically, this was due to the fact` that the centripetal forces set up forced the air entrapped in the pockets against the walls of the pockets instead of laterally into the tubes.

The present invention is designed to overcome these difficulties. It involves the use of thermal elements'with the tubes and power means so related to each other that in every part of each the centripetal forces acting against the lighter fluid willhave a component in the direction toward the center of rotation. The method also involves the use of a single axis of rotation.

For carrying out this method, a mechanism is provided also. This mechanism involves a rotating shaft extending radially from which are tubereceiving members. At the ends of the tubereceiving members are provided heads. These heads are designed to communicate several thermostatic elements, and the thermostatic tubes are adapted to extend along the receiving members. The rapidly moving parts of the machine are designed for a minimum of air resistance wherefore they may operate with a minimum of power consumption.

It is a primary object of the invention to provide a novel method of making thermostatic elements and for eliminating therefrom, by centrifugal force, undesirable fluids. In the discussion to ensue, for simplicity, reference will be made to the elimination of air from liquid-filled thermostats. It is to be understood, however,

that air and liquid are merely representative of any fluids of different specific gravities separable by different responses to pressure applications.

It is a further object of the invention to provide a method for making thermostats involving 5| the elimination of pockets where there is no pressure outlet toward the axes of rotation upon application of centripetal force thereto.

It is a further object of the invention to provide a mechanism having a radially extending hollow arm adapted to receive a thermostatic element 5 and to hold the same in such relation as to effect the method outlined above.

It is a further object ofthe invention to provide a hollow radially extending arm adapted to receive a plurality of thermal elements to support 10 the same while preventing movement of the power means thereof, with the thermal elements extending at an acute angle with respect to the radius comprising the axis' of the tube-receiving member. l 5

It is a further object to provide a structure of this kind compactly designed and shaped to offer a minimum of air resistance during its operation.

In the drawings:

Fig. 1 is a plan view of the device. 20

Fig. 2 is an elevation partly in section.

Fig. 3 is a plan View of one of the heads closed.

Fig. 4 is an elevation of one of the heads partly broken away.

Fig. 5 is a horizontal section of one of the 25 heads taken on the line 5-5 of Fig. 4.

Fig. 6 is a vertical section of one of the elementreceiving members taken on the line 6-6 of Fig. l.

The structure disclosed includes a base I0 upon which is supported a motor I I, the support means 30 comprising the bracket I2. A housing I3 surrounds the motor. Ihe brackets I2 and housing I3 are secured to the base or foundation I0 by means of screws I4, or the like.

The motor has a shaft I5 standing from the top 35 thereof. To this shaft, a vertical extension shaft IG is secured by means of a screw I1. The extension I6 rests upon the upper race I8 of an antifriction bearing I9.

At its upper end, the extension I6 has a plu- 40 rality of pairs of opposed ears 20, these ears extending radially from the extension. In the present illustration, four pairs are shown.

Attached between each pair of ears 20 is a tube-receiving element 2|. A dog 22 extends from the inner end of each member 2| and is secured between the ears 20 by a pivot screw 23. The dog 22 has a jack-knife construction providing an edge 2| engageable against the extension I6, as shown in Fig. 2, whereby the downward pivotal movement is limited to approximately that shown in Fig. 2. The upward pivotal movement is not so limited but ordinarily will not exceed a right angle relationship between the axes of the member 2l and the extension I6. As

shown in Fig. 6, the members 2i are streamlined so ythat in cross-section they have a tear drop shape with a rounded leading edge and a sharp trailing edge.

To the outer end of each of the members 2i is secured a head 2t. This head may be held onto the member 2i by such means as peening Aover the ends of the tubes 2l, as shown in Fig. 5 at 2l.

- Each head includes an inner member 2@ and an lli outer member 2Q pivoted together as at lfi. Referring to Fig. 4, it may be seen that the member 28 has spaced ears 3l between which nts an extension 32 of the outer member 29. The pintle 3@ then passes through the ears 3l into the member 28. The two members 2S and and the joint between them, are so interiitted as to provide smooth outer surfaces.

The inner member 2t is hollow to communicate with the interior of the member 2 i. lt is provided with a plurality of round seats 3K3 from which extend grooves 35 leading to the interior of the element`2l. The seats 3d are shaped to fit the particular thermostat elements being employed. Upon the outer member 29 are secured plugs 36 that are adapted to fit against the power means of the thermostats and prevent movement thereof under the action of the centrifugal forces. In the present illustration, it may be seen that these plugs 36 extend at an angle to the axis of the members 2 i.

Toward the rear end of the members 2d and 29 a securing means is provided. This includes a thumb nut 40 operating on a threaded extension 4| of a lock member. Thelock member has a dog 42 engageable over a ledge 43. The upper portion of the lock member is rounded at 44 to fit in a correspondingly rounded cut-out 45 in the outer member 29. When the nut is loosened, the rounded portion 44 pivots in the cut-out 45 to free the dog 42 from the ledge and permits openingof the head. When the screw is tightened with the dog engaging the ledge, the head is closed firmly and the plugs 36 are seated snugly against the diaphragms.

The thermal means here shown comprise tubes 41 at the outer end of which are secured power means. Each power means involves a cup-like member 48 inside of which is secured a ilexible diaphragm member 49, also cup-shaped. Preferably the diaphragm is secured to the outer member 48 by Welding together their contiguous edges. The tube 41 communicates between the diaphragm 49 and the cup 48 by entering at an angle through one corner of the cup 48, as shown. The cup and diaphragm are provided with a dome 50 and may be corrugated, as desired, preferably with radial corrugations. Further details of this particular' type of diaphragm and elementare given in my copending application Serial No. 110,797, filed November 14, 1936,' but it is to be understood that its description here is merely illustrative of one type of power means to which the method and mechanism are adapted.

It will be seen that the seats 34 are at an angle to the axis of the member 2|. 'Ihe plugs 36 are at a corresponding angle to the latter, and fit down against the diaphragm 49 to prevent their lifting away from the cups 48 u'nder the centrifugal action.

'I'he present method and mechanism, while of general application, are particularly adapted to use with diaphragm Ltype thermal eelments, which thermal elements have a so-called solid charge. That is to say, the entire system is charged with a fluid that remains liquid throughout its opermeans.

ating range. Therefore, the force tending to separate the diaphragm from the cup element (or, in case two diaphragms are used, the force separating the two) is of relatively high value and is not elastic as is the case where gas-charged elements are used. It is, consequently, absolutely essential that all gas be eliminated from the assemblies, since the presence of even a microscopic amount completely over-throws the uniformity of operation of the thermostat.

In the present method of designing and filling thermostats, the rst step may be said to be the formation of thermal elements with the tubes extending angularly from the power means, as is Shown. The shape of the power means is such that all parts thereof are located outwardly of the tube. The angle between the power means (and seats 35i) and the axis of the tube 4l is such that, upon operation of the centrifuge with the tubes substantially radially thereof, there are no pockets present that could prevent the centripetal passage of the air from all parts of the power means into the tube.

Having the thermal elements thus designed, they are filled with liquid and put into the tubes 2i with the power means or diaphragm cups located in the seats 34 and the tubes 41 extending out the grooves 35 and thence substantially radially inwardly of the rotating elements 2l, the inner ends remaining open. The outer element 29 of the head is then closed, the plugs 36 coming down against the diaphragms 49 in such wise as to maintain the said diaphragms snugly against the cup-shaped members. The fastening means is then engaged and the motor Il started. Upon rotation of the arms 2|, centrifugal forces are set up in the liquid filling the entire thermal assemblies; that is to say, the tube and power Corresponding centripetal forces act against the lighter air entrapped within the assemblies and force this air all into the tube 41 and thence along the tubes, where it escapes out their long open ends. Rotation about a single axis is all that is necessary. After purging the assemblies of air, the machine is stopped, the

thermal assemblies removed, and the tube ends sealed over.

The particularA mechanism described has certain additional advantages. The arms 2| drop down, as shown in Fig. 2, when the machine 1s stopped. Consequently, when the assemblies are put into place in these tubes, the open end is at a greater elevation than the closed end. Hence, the liquid within the assemblies will not spill out, Of course, as the machine starts rotating, the arms 2| swing up until they are at right angles.

Since the arms 2| may be as much as 7 or 8 ft.

p long their outer ends travel at high linear velocities even though the motor may be revolving at a relatively low speed. To reduce the air resistance, the tubes 2| are streamlined and the heads, including both the inner members 28 and the outer members 29, are streamlined about both vertical and horizontal axes. By this means, the power required for operation of the machine has been reduced as much as one-half. 'I'he fastening means 40 is of the quick-acting type for greater eiliciency.

It may thus be seen that there has been provided a novel method of making thermostats involving the elimination of air therefrom by a centrifuge rotatable about a single axis of rotation, but, nevertheless, completely effective in the purging of the air. The method is particularly applicable to diaphragm thermostats but its use is more general as is obvious. In addition, a means or mechanism has been provided of particular efciency for carrying out the method. As noted, in the claims to follow, the terms liquid and air are merely representative ofany two substances having different specific gravities,

What is claimed is:

1. In a method of purging a container consisting of a pair ofl intertted cup-like members having a space therebetween and an outlet adjacent their bottom portions, the steps of rotating the container about an axis, maintaining the axis of the cup at an acute angle to a radius to 5 the axis of rotation with the open end of the cup facing away from said axis of rotation, and the outlet nearest of all parts of the container to said axis of rotation, and thereafter closing said container.

2. In a method of purging assemblies consisting of a pair of intertted cup-like members sealed together around their sides to form a chamber between them, and a tube communicating within the chamber and extending therefrom, the steps of rotating the assemblies. about an axis of rotation, maintaining the tube with its passage extending continuously inwardly away from said axis toward the same, and maintaining the chamber entirely relative to the outer end of the tube, beyond the same andwith all passages of said chamber having such of their wais as are on the sides of such passages toward the axis, extending continuously outwardly from said tube, and thereafter closing the tube. 5 3. In a method of purging a container consisting of a pair of cup-like members closely interfitted and normally contiguous throughout, one of which is flexible, and having a tube communicating between said members at the junction of bottom and side walls, the two members being sealed together about their contiguous side walls, the steps of rotating the container iiled with liquid about an axis of rotation, maintaining the tube with its passage extending continuously inwardly toward the axis of rotation, maintaining the cup-like members so that their axis extends at an angle to a radius of the axis of rotation, with the bottom walls extending at an acute angle to the said radius and the open end of the cuplike members outward, with the entire cup out beyond the end of the tube, and maintaining the fiexible cup-like Amember against movement in response to centrifugal force, and thereafter closing said'tube.

4. In a method'of purging liquid filled assemblies consisting of a container formed of two cuplike members the inner of which is flexible on its bottom portion to move toward and away from the outer one, which are sealed about their side walls, and which have a tube extending from the outer one at the junction of side and end Walls, the tube communicating within the space between the members, the steps of applying a force onto the liquid at the remote end of the tube while 5 maintaining the tube so that its passage extends continuously outwardly from said remote end in the direction of the force, maintaining the cup-like members so that their axis extends at an angle to the direction of force with the outer cup toward the direction from which the force is applied, and the bottom walls also extend at an angle to the direction of force with the entrance of the tube at the point in the container nearest the direction from which the force is-applied, and during the application of such force, holding the cup-like member to the force, and

exible bottom of the inner against movement in response thereafter closing said tube.

5. A centrifuge including support means to receive thermal elements comprising tubes and chambers extending laterally from said tubes, means to rotate the support about an axis, means on said support means to hold the tubes radially of said axis, and means to hold said chambers at an angle to said tubes.

6. A centrifuge including a base, a rotating shaft on the base, support means extending outwardly therefrom to receive a thermal element having a tube and a laterally extending chamber, a head on said support means, said head having a seat to receive the chamber of said thermal element, the seat extending at an angle to said support means of such degree as to overcome the effect of any pockets in said thermal eleme'nt and to prevent their obstructing centripetal forces produced upon rotation of said support means.

7. A centrifuge including a shaft of rotation, a hollow arm extending radially of said shaft, and a head on said arm, said head having therein a seat to receive a thermostat expansion chamber, said seat extending at an angle to the said arm, of such value as to deflect centripetal forces produced by said centrifuge in said chamber into said arm.

8. A centrifuge including a shaft of rotation, a hollow arm extending radially therefrom, a head on saidarm, said head including a section attached tc said arm and having a thermostat receiving seat, a second section pivotaily mount ed to cover the first, and having means therein to engage a thermostat on said seat and hold the same against movement relative thereto.

9. A centrifuge including a shaft of rotation, a holiow arm extending radially therefrom, a hol-u low head on said arm, said head having a plurality of seats to receive expansion chambers of thermostats, the tubes of which extend into said hollow arm, and said seats extending at such an angle to said arm as to overcome the effects of pockets in said expansion chambers upon centripetal forces produced by said centrifuge.

l0. A centrifuge comprising a vertical shaft, a plurality of arms, means attaching said arms to said shaft radiaily thereof for limited oscillatory movement in a verticai piane, a head on each of said arms, said head being adapted to receive diaphragm expansion chambers of thermostatic assemblies, and said armsbeing adapted to receive the tubes thereof, each said head having seats to receive said chambers, said seats extending at an acute angle to its respective arm, and means extending toward said seats to hold said chambers against expansion under the centrifuge action.

11. In a centrifuge adapted for use with assemblies consisting of a pair of members sealed together to provide a sealed chamber between the members, and one of which is flexible, with a tube communicating with the said chamber, a member adapted to be rotated about an axis, means supporting the tube so that its axis extends continuously outwardly from the axis of rotation, and a seat on the member arranged to hold the sealed members outwardly relative to the axis from said tube, and with the walls thereof toward the axis all sloping relative to a radius to the axis and forming a continuous baffle extending to the tube with no pockets.

12. A centrifuge adapted for use with assemblies having a pair of cup-like members sealed t0- gether around their side walls, one of which has a flexible bottom "wall, and with a tube communicating into between said chambers and attached at the junction of bottom and end walls, a rotatable element, a member extending outwardly from the rotatable element to support the tube so that its passageway extends continuously outward from its free end to its juncture with the cup-like elements, and means on the outwardly extending member to support the cup-like members, said means being adapted to hold the said cup-like members with their axis at an angle to a radius of rotation and so that they extend continuously outward from the tube, means holding said cup-like members to the support means, and means preventing expansion of the flexible bottom wall.

13. .ilv centrifuge adapted for use with assemblies having a pair of intertted cup-like members sealed together around their side walls, the inner cup-like member having a flexible bottom wall, and a tube extending from the outer cuplilre member at the junction of bottom and side walls at an angle to the axis of said cup-like members, said assemblies being filled with liquid, the centrifuge having a rotatable shaft, an arm extending outwardly from the shaft in a radial direction, and adapted to hold the tube disposed therealong with its passage extending continuously outwardly, a support on the outer end of the arm to receive the cup-like members and hold them with their axis at an angle to a radius through the arm to the axis of rotation, and with the walls of the cup-like members extending continuously outwardly from the tube, and means on the arm adapted to be fitted tightly against the flexible bottom wall and to maintain it in contact with the other bottom wall.

14. A centrifuge including a support means to receive a thermal element comprising a tube and a chamber extending laterally from the tube, means to rotate. the support about an axis, said support means being adapted to hold the tube so that it extends continuously inwardly towards the axis without reentrants, and means to hold said chamber at an angle to said tube.

LAWRENCE M. PERSONS. 

